umm.... they sure as hell fixed the slow zones on the Blue line from Belmont to O' Hare. I took it for the first time in a while a couple of days ago. Those old trains were moving.

I've always wondered why Chicago and Rockford don't work to be more connected. There is ROW all the way to Rockford, through Marengo and Belvedere. Not exactly high-population centers, but bigger than Harvard and not far off Oswego. I'd think extending from Elgin with the MD-W line would make the most sense if they're using exist ROW. That picks up Marengo and Belvedere and could bring it right downtown Rockford. It seems like a few express trains between Rockford and Chicago could be scheduled such that they could make the trip in under 90 minutes - maybe as low as an hour if the speeds on the parts between Rockford and Elgin were upped beyond the current 75mph limit most of Metra has.

As Amtrak redevelops the Great Hall building they'll start getting rent from offices and retail that would offset their lost event revenue, a bonus that it's also a much more predictable revenue stream for them.

From offices around the great hall?

Above. The office floors have been unused for decades. Amtrak is already in the process of environmental remediation (asbestos and lead paint) and mechanical upgrades.

Amtrak Black Hawk service is supposed to resume in 2014 over the CN. Rockford and Belvedere REALLY wanted the UP route from Big Timber for both Amtrak and METRA instead but the IDOT study said the costs were 3 times more than using CN. Metra would have to start it's own negotiation with CN for trackage rights and get the new counties to join the RTA.

This is the ROW that runs SW from Union Station, then veers NW through Berwyn, running alongside the Loyola Maywood campus, Bloomingdale, South Elgin, etc... correct?

EDIT: Google is our friend. Study here: http://www.dot.il.gov/DPIT/Chicago-R...L%20101208.pdf

also: http://members.trainorders.com/dr04/BlackHawk/

Unless Amktrak can negotiate a better travel time between Chicago and Rockford, it seems hard to justify the investment in a new once-daily rail service when the intercity bus industry could otherwise carry this market.

Correct.

I have no doubt that Amtrak knows they have to get those times down and that certainly will be a focus of their negotiation with CN. They are also going for multiple daily trips instead of just one.The prospects for Metra service along the same corridor are going to be more difficult, which is why Rockford and Belvedere desperately wanted the UP route for Amtrak so Metra service could come on later with a lot less hassle.

Once the rebuild project starts on the Jane Addams the Black Hawk will be selling out as an already congested road trip becomes almost impossible.

Using CN might offer slightly better travel times, but it's worse from the perspective of regional connectivity. The Black Hawk will be operating on a line without a single connection to Metra service until one reaches Chicago. Not only that, but there is no stop in the vast territory between Elgin and Chicago, while Rockford gets TWO stops, and due to Byzantine arrangements with the RTA, Amtrak cannot pick up passengers on Chicago-bound trains within the RTA service area (i.e. South Elgin). I don't think this applies to all Amtrak lines, since you CAN go from Glenview to Union Station on the Hiawatha, but the price is double that of Metra.

I thought we were trying to build a connective system where Amtrak passengers could switch to Metra at an outlying station to reach any number of suburban destinations? Co-locating commuter and intercity rail is just more efficient, since it allows the two services to share responsibility for the maintenance and expansion of tracks and facilities, and provides the greatest mobility to each individual passenger.

I don't have an opinion on whether Belvidere or Genoa should get Amtrak service, but east of Elgin, the train should operate via Metra.

^ I wonder if the folks of FlyRFD.com doing anything proactive about this. Not that the western suburbs lack good airport access, but there are some incredibly cheap fares out of RFD that people living downtown - or people seeking to visit Chicago (Lolla, Pitchfork, students, on and on) - would jump on if highway congestion weren't a potluck proposition.

One of the original routing options went past RFD. I think they ruled it out due to a high capital cost and a 6-mile detour via Davis Junction, as well as the massive unreliability issues that typically come with running (ir)regular train service over poorly-managed short line railroads.

I agree with you that an RFD station would be much better choice for suburban Rockford than the current Alpine Road location. As is often the case, though, the terminal was built on the opposite side of the airport from the tracks to avoid a grade crossing, so getting from the terminal to the hypothetical platform would require a bus.

Also all of the western suburbs are gonna flip shit when they find out that even more trains are being added to the line.

CP is now again in possession of all of the Elgin Subdivision including the part it sold off in the 90s that recently belonged to the IC&E when the IDOT study was done. The route has a number of advantages that the CN and UP does not. For one the entire length to Davis junction was formerly double tracked and some portions remain so. In addition to running right by RFD a connection to CN already exists just south of the Rock River and the CN bridge across it was also formerly double tracked.

edit: dp

Intriguing. I guess the only stumbling block is capital cost, then - even Genoa would still get their much-desired rail service.

I'm interested to see what kind of schedule IDOT can work out with CN. I wonder if there is the will to run service to Rockford on semi-commuter frequencies? Dubuque service could remain less frequent.

It seems like the line should be able to support a fairly robust level of passenger service due to the relatively low amount of freight traffic. Looking into the future, perhaps we can get 2 or 3 suburban infill stations. Glendale Heights, South Elmhurst, and the Hines VA/Loyola Medical seem like the best choices.

It will be compatible with all the potential future plans for the Red Line. The reconstruction of the Loyola stop is going to be the first phase in all of the plans and Loyola's capital planning department is working hand in hand with the city on the reconstruction. LUC hates the current configuration as they feel it damages the image of the university because it is so grimy and dangerous. Not only does it constantly feel like you are going to be mugged when you are in that station (despite the fact that it is a very safe station), the crossing situation on Sheridan is extremely hazardous. Loyola Students are often in danger of being hit when they try to play frogger to catch the next train. That bulky viaduct just further inflames the situation as no one can see what's going on on the other side of it. All in all its a bad situation that makes Loyola nervous, they don't need any headlines about a Loyola student getting pancaked on campus.

Anyhow, all of Loyola's new facilities are being designed with the reconstruction of the viaduct and station in mind. I believe part of the plans are to elevate the structure and open up more of the campus between the new student center and Sheridan road which will allow Fordham Hall/Grenada Center more direct access to campus under the tracks.

$7.3 million OKed for downtown ‘bus rapid transit

http://www.wbez.org/story/story/city...own-brt-96580#

Chicago Commits to Downtown Bus Priority


February 22nd, 2012

By Yonah Freemark

Read More: http://www.thetransportpolitic.com/2...-bus-priority/




http://www.thetransportpolitic.com/w...ator-Route.png




For lack of funding, it will be a long time before any such routes see the light of day. In the meantime, painting a few bus lanes and offering existing lines priority at signals represent a reasonable step forward.

http://www.thetransportpolitic.com/w...tor-Routes.png

As long as you allow automobiles to make right turns from "bus lanes" the lanes are rendered useless as the autos have to wait for legal crossing pedestrians to clear, and then wait for the jaywalking pedestrians who ignore the "don't walk" signals.

DH

The overall benefits seem pretty negligible except for the new bus depot on the south side of Union Station. Canal is a total frigging nightmare with CTA/intercity/taxis/livery/private cars all over the place. Hopefully the city can better organize loading areas on Canal and Adams for each service.

^ About Canal Street, how possible would it to use portions as a double-decked roadway? I think between roughly Harrison and Taylor it is effectively elevated and in theory could be a two-level roadway, and parts of it in the congested Madison-VanBuren stretch seem similar to that (and are closer to the elevation of the river bridges than they are to the elevation of Clinton). I assume there are station concourses underneath between Adams and Jackson, but I don't know what's underneath the rest of Canal around there.

Single transit card for CTA, Metra, Pace closer to becoming reality
 

http://news.medill.northwestern.edu/...aspx?id=200925


Single transit card for CTA, Metra, Pace closer to becoming reality

BY MARISA PAULSON

FEB 22, 2012

Those commuters who use a combination of Chicago’s transit agencies—CTA, Metra and Pace—soon will only have to carry one single “open payment” smart card, or maybe even just their smartphone, instead of juggling cards, passes and stickers to transfer.

That day is a few years away, but the Regional Transportation Authority voted Wednesday to develop and implement a regional fare model that brings them much closer to that goal of seamless transfers.

One expert endorsed the move on Wednesday.

“Hopefully, they have enough time to think about it, meet, agree and do it. It can be only beneficial for riders of all service boards,” said Paul Metaxatos, associate director for research programs and research assistant professor at the University of Illinois at Chicago’s Urban Transportation Center.

Last July, Gov. Pat Quinn signed legislation giving the RTA until 2015 to develop a fare card usable on all three transit systems. In response, RTA sought bids in the fall and selected the TransSystems Corporation team, the lowest bidder, to consult on a regional fare model. The team’s sub-consultants that will take care of 27 percent of the project are Cambridge Systematics Inc., CR Market Surveys Inc. and cmQue Inc.

The total cost of the 15-month contract that began Wednesday is $416,165, but 80 percent will be provided by the Illinois Department of Transportation through a Unified Work Program grant.

Since RTA is grappling with very different fare models—for example, Metra fares are distance-based while CTA and Pace fares are fixed—months of surveys and analysis are required to determine ridership and revenue impacts.

“It’s a complicated issue, obviously, because the fare systems for the three agencies are different,” Metaxatos said. “They have to agree how the revenue will be shared and develop an instrument that will accommodate their agreement.”

The regional fare model will be built in modular fashion, with stand-alone CTA, Metra, Pace and interagency modules, which will allow each service board to use its stand-alone module for internal budgeting and planning.

While this is an exciting move for Chicago commuters, the city is frankly a little late to the universal fare card party.

Hong Kong has the “Octopus” card, which was introduced in 1997 and can be used on the city’s railways, buses, taxis, trams and ferries, as well as for parking and many convenience and retail stores.

Paris’ “Navigo” card was introduced in 2001 and can be used across several transit agencies on the city’s metro, buses, trains and even rental bikes.

And London’s “Oyster” card was issued in 2003 and the 43 million cards that have been issued are good for journeys on the Tube, bus, tram, Docklands Light Railway, London Overground and most National Rail services. More than 80 percent of all public transit trips in London are made using an Oyster card, according to a Transport for London release last year.

But regional fare cards aren’t only found across the pond: Washington, D.C.’s SmarTrip, first sold in 1999, was the first contact-less smart card for public transit in the U.S. While they could only be used on the Metrorail system at first, they soon were be able to be used on Metrobuses, as well as buses and vans across several transit agencies and some parking garages.

The San Franciso Bay Area’s “Clipper” card – formerly known as TransLink – was tested in 2002 and introduced in its current form in 2010. It can be used for seven transit agencies in the Bay Area. By the end of last year, 1 million Clipper cards had been issued, according to San Francisco’s RTA equivalent, the Metropolitan Transportation Commission.

Ian Savage, associate chair of Northwestern University’s economics department, has studied urban transit for decades, often focusing on revenues, costs and optimal fares.

Savage, who is affiliated with the university's Transportation Center, said that a single transit card has been a goal ever since the RTA was established back in 1974.

“Here we are, 30 or 40 years on, and you still can’t even link up in any effective way from CTA train to Metra to bus on a common card,” Savage said. “It’s kind of an embarrassment that we don’t yet have this. I think there have been some technological issues, but issues that are not insurmountable.”

Savage said that Metra may be to blame for the years of inaction on a single transit card.


CTA introduced the smart Chicago Cards in 2002, followed by the Chicago Card Plus in 2004. Savage said the cards grew out of RTA initiatives. Metra didn’t even accept credit card payments at stations until 2010.

“Metra has clearly been a sticking point here,” Savage said. “I’m in favor of the distance-based fares, but I think Metra has been a very conservative agency as far as fare technology is concerned.”

Savage said he just hopes that RTA and its service boards can move fast enough. He said that credit card companies are examining small payments, which would allow public transit riders to pay their fare with the same card they already use for larger purchases.

“In some ways, they could see an effective credit card company doing this for them,” Savage said. “The more that they dally, the more likely they may get taken over by technology.”

You're right that Canal is at an artificially high level because it has to cross the approaches for the river bridges. There's actually one track underneath Canal - Union Station comes as far west as the centerline of Canal.

http://img831.imageshack.us/img831/2080/canalm.jpg

^I thought one of the tracks actually came under Canal, and I looked up those same diagrams this morning, but I'm not sure those dotted lines were ever actually built. I think that former baggage tunnel that's now a pedway to the parking garage might be the only intrusion under Canal—other than the passageway from concourse to headhouse waiting room. That, of course, is a pretty big obstacle to roadway use.

Incidentally, Canal is scheduled to be completely rebuilt in the next few years by CDOT. I think that's one of the impetuses for the Union Station master plan.

I was looking for a better diagram earlier, and now I found it... Tracks 1, 2, 3, and 4 are directly under the ROW of Canal. Track 6 straddles the eastern edge.

As much as I like the megalomaniacal implications of an even bigger Union Station, I just don't think we need an expansion. It would be a far better use of dollars to change operating practices in order to turn around Metra trains faster - even if they have to lobby the FRA for a waiver or rules change. Shifting SWS to LaSalle will free up capacity too.

If they do rebuild Canal, supports should be shifted to the edges where possible so that there are no necessary supports in the center of the street. Later, the area underneath could be excavated for through platforms, either at the level of (i.e. severing) the Union Station concourse or one level below.

http://img706.imageshack.us/img706/511/cus1h.jpg

Isn't Metra the only system that isn't part of a unified fare card? I use a ChicagoPlus card on everything except Metra. Theoretically couldn't they just implement this in a matter of weeks?

Just looking at the 'newer' portion of Union Station gives me a headache. Maybe it doesn't need to get bigger in trackage, but the layout and congestive nature is awful. I take Amtrak regularly, I'm embarrassed as to what visitors first see...and what they are likely to never see, the Great Hall.

If I were to re-design based off this diagram, I'd move Metra and Amtrak offices into the older Union Station...anywhere that says "vacant." Also located baggage claim areas into the closest vacant space near the tracks and close by those service corridors. Create parallel ticket counters that flank each side of the circulation datum between old and new terminals, and then entirely open up the rest of the space with waiting, surrounded by a secure trackside circulation ring. BTW, notice the major security flaw with trackside escalators which lead upstairs to the food court? Ideally, the trackside circulation ring should be for ticketed passengers only, and the upstairs should only accessible when they exit the secure area.

Does anyone think it's possible to merge the food and waiting areas to one floor to raise the ceiling height? It would eliminate the cave like feeling and the warren of passageways and concourses would be resolved by opening the space up. I think the future of Union Station needs to be thought of like an airport terminal.

The solution is painfully obvious. All the vacant areas around the Great Hall become lounges, the concourse becomes open again. I'm not sure how intensively the sub-basement is used, but they could depress the floor of the concourse to make it more spacious.

Be careful what you wish for. As long as Amtrak continues to treat boarding as a pseudo-airport experience, I think it will be hard to draw passengers very far away from the gates. Even worse, imagine the entire passenger manifest for the Chief shuffling from the Great Hall through the underpass and out to the gate, as commuters rush in to board their afternoon trains. As disappointing as the 1991 remodel was, it was driven by the serious problem of separating the commuter flows from the Amtrak boarders.

There are real questions that need to be answered, real decisions to be made and equipment to be ordered, but in theory probably 3-6 months could happen if Metra was under enough pressure to make decisions quickly and the RTA ordered things quickly. More realistic would probably be 6-12 months, maybe as long as 18 months or more.

There are solutions for all the sticking points, but decisions need to be made on which solutions are most suitable. With the CTA you pay before or while boarding and it doesn't matter how long you're on the train or bus. With Metra you pay either before boarding or after you've boarded and get in trouble if you stay on longer than you'd paid for. The difference is not difficult to understand conceptually, but when trying to design a uniform payment system there are processes and equipment changes that would need to happen.

That's why I'm not suggesting the Great Hall be waiting space in my previous post. It would be okay to move baggage claim and any ancillary support services to that area, but it should not be the place for departing passengers. Actually the waiting areas are not technically for ticketed passengers. Trackside perimeter circulation is. You can maintain this configuration, and create gates between the perimeter trackside circulation and waiting where passengers are checked by agents. It's not much different than the current process.

Interesting you mention a sub-basement ardecila. I don't think dropping the floor level is the most economical or practical option. The last thing we want to do is have passengers go down, then back up. When planning terminals and stations, you generally want to try and keep all related program on one floor level to allow for future flexibility. For example, during the holidays you may have to create temporary queues to manage passenger demand. If you have a ton of ramps to take passengers up to trackside circulation, you might have some issue setting up your queues.

It might be possible to use that sub-basement to run your mechanical under floor. Instead of above ceiling in the basement. It might give you a couple more feet of height, but probably won't fix the issue. I'd rather see a double height space with the restaurants arranged in a more logical layout...perhaps on a mezzanine that overlooks the waiting areas. It allows public access to food court areas, but still maintains some separation from the waiting areas. A new layout would also permit relocation of escalators away from trackside circulation.

What I'm suggesting is a pretty big (and expensive) overhaul of Union Station, but I think it's needed and will be worth the effort in improving passenger rail experience.

Since all systems are pretty much computerized, even when you purchase tickets from an agent, you could select your destinations or number of rides and either pay with credit/cash or wave your ChicagoPlus card. I have a SmartCard for DC and it works the same way. Bus fares are flat rate, Metro rates depend on distance. Now of course you swipe in/swipe out in DC, but the idea here isn't really different from Chicago. Point is you need an electronic terminal to either print a ticket or "check in" with a plus card via a handheld device carried by an agent.

Just order the equipment, train the conductors on the technology, done.

I guess I never realized the extent of the Canal viaduct... Madison to Taylor! Wow. How wide is it? On Google Maps it looks like the street is about 80-100' wide. If it's through tracks they're after, why not just build them under Canal Street? Surely they could fit at least three or four tracks under there (two platforms.) Much less expensive than WLTC craziness under Clinton or demolishing 222 Riverside.

Canal ROW is 80 feet wide. But how would you connect the concourse to the headhouse if you have tracks under Canal?

By the way, I understand Canal is the current preferred alternative for a WLTC tunnel. But that would go much deeper than just adding some through tracks at the same level as the current tracks.

But Metra doesn't have faregates. So you have to have some sort of RFID validator carried by the conductor.

2 or possibly 4 through tracks would be one level below the concourse-headhouse connector. To save cost and simplify excavation, you would probably want to make the tracks as close to the surface as possible, so whereas most of the Canal platform would be somewhat spacious, you'd have a low ceiling where the concourse-headhouse connector passes across on a bridge.

Serious questions need to be considered if we're gonna build anything like this. Does there need to be clearance for Metra's gallery cars, or can we live with smaller tunnels and less-tall rolling stock? The difference could be billions or at least hundreds of millions of dollars.

http://www.thetransportpolitic.com/2...-bus-priority/

Chicago Commits to Downtown Bus Priority

http://www.thetransportpolitic.com/w...ator-Route.png

How much clearance is there under the Canal viaduct? Could they dig out a few feet under it to lower the tracks, and then design the viaduct to have the thinnest possible substructure, and wind up with enough clearance for both the connector AND the tracks? I'm guessing probably not.

It's probably easiest to raise the height clearance through cutting out structural depth as opposed to long sloping track approaches to gain maybe inches. I think Canal is basically your traditional steel bridge girders and could be replaced with slab and column like Wacker Drive.

For vehicular traffic, unrestricted clearance is anything above 14'-6." I think a good clearance for passenger rail is around 18'

Metra bilevels are 15'10". The slab on Wacker is 13" thick. The "ribs" functioning as the beams increase the total thickness to 2', but the passageway could be built between the "ribs". So:

13" slab
7'6" clearance for the connecting passageway
5" thickness for the floor,
16' from the bottom of the floor to the top of the rail

That makes a bare minimum of 25' from top of rail to surface of Canal Street.

Not sure what the current clearance is, but slab track can be pretty low profile. Shaving a couple feet of dirt could help if necessary. Orders of magnitude cheaper than WLTC. Unlike WLTC, this does not address congestion at the northern throat, but on this thread I've seen folks speculate that at least a fourth track might be possible.

Lol! No way you can allow 2 inches of breathing space for train clearances. Even if you don't run Exhaust ducts over tracks there needs to be space for conduit runs and likely fire suppression since these are semi occupiable spaces.

The passageway as built is much taller than 7'6", and the floor is roughly at the same level as the Great Hall and the platforms. "Shortening" the height of that passageway means that passengers would have to go up a ramp and then back down again, which compromises the whole design of the station.

I think the passageway height needs to stay at the same elevation it is now, roughly 16'. You also need several feet of clearance beneath that for safety if you ever want to electrify the lines with modern AC technology. Low clearance at overpasses is the main reason why Metra Electric still runs 1500v DC where you only need a few inches of clearance for insulators.

There's another concern about using the bilevels at the through-platforms. For efficient through-running, you want to clear the platforms quickly. Bilevels will dump tons of people onto what will probably be narrow platforms, and then they need to walk down the platform to a vertical access point (stair/escalator). Since there is no mezzanine, these access points will be far apart. All this stuff works fine at the existing terminals, but when you need to bring in a new train every 5 minutes on the same track, you need to design everything differently.

If you think 5 minutes is unrealistic for Metra, note that even SEPTA sometimes runs 5-minute headways on each track in the Philly tunnel. I'm all for identifying cheaper ways to build the damn thing, but we need to design it for 60 years of growth, electrification, and potential regional rail like an RER or S-Bahn.

http://farm7.staticflickr.com/6046/6...166b75cf_z.jpg

I'm not sure what a thru-way rail line at the western part of the station would achieve. You would need some way to have passengers board and get to the station level. Given the current architecture, you'd have to have ramps going from the Great Hall passenger walkway down to the newly recessed platform level. The incline itself would need hundreds of feet to get to the platform level.

Here is an interesting idea that this person did as his thesis for Union Station.
http://www.coroflot.com/rikakooy/The...-Union-Station. I like the way that he opened up the floor plan, and has a grand staircase that lets you look toward the Great Hall. However, I think this design suffers from not enough bathroom space, as well as not a large enough seating area for Amtrak.

I was wondering if it is possible to create an Amtrak level underneath the concourse level, so that Metra riders and seating is at the concourse level, and Amtrak has the level below. This level would have an enlarged seating and security level. HSR would have new rails that would be underneath this level. So, the Amtrak level has access to go down the HSR platforms, and access to go up to the concourse level. Regular Amtrak trains would be accessed at the concourse level. I am concerned that such a layout may have issues with a fire evacuation. I have started to make drawings on this layout based on the thesis statement project. If anyone is interested, I'll try to post them.

Why would you need ramps? You'd have a combination of escalators, stairs, and elevators to go from concourse level to the new platforms.

To be honest, I think we should follow the Paris model, and any new through-platforms should be used for Metra service while Amtrak service continues to terminate. Shifting Metra to through trains will clear up virtually all the "capacity" problems of Union Station (the small concourse is a different matter).

As a start, join the BNSF and Milwaukee District together, so that one BNSF train would run to Elgin and the next to Fox Lake. Right away, you've cleared up at least half the platforms at Union.

Well, I guess it depends on the arrangement. I'd prefer a waiting area with gates, instead of everyone mobbing the trackside corridor through one doorway. Unions single biggest problem is cross circulation. The traditional multi level designs of waiting and platform areas needs to change in modern stations to a single floor layout. No one likes going up and down escalators with luggage. There is ADA issues, ramp space issues, elevator location issues, vehicle and heavy equipment issues with dropping the waiting room below track levels. You should only have to descend from street level to basement to board trains, and this can easily be done.

This is a pretty exciting discussion ... I can't believe the Canal rebuild was not more widely known (by me and I suppose most people) until now. It seems there is so much potential and I hope some productive use is found for every cubic yard of space beneath street level, whether rail, roadway, bus, service drive, or ped concourse related. I really hope CDOT (and every other involved entity like Amtrak) is being creative and aggressive about it.

It seems to me from diagrams that the canal viaduct is actually only half the width of Canal for most of its length, except for the block between Adams and Jackson right in front of Union Station.

Right. Short of putting all Amtrak trains on the two river tracks, the only way to keep everything flat for Amtrak is to terminate Amtrak at Union. Deeper platforms should be for Metra, just like they are at Gare du Nord.

This, of course, is exactly what Thomas Rodd created at Chicago Union Station, until Amtrak closed the taxi drives after 9/11. You walked on one level from taxi through Great Hall to ticket window to concourse to train.

Orulz, what diagrams are you looking at? The old descriptions of the Canal viaduct construction make it sound like a full-width viaduct, and that's certainly my memory at places like Cabrini where you can see underneath.

http://i39.tinypic.com/okxvrs.png
Google Street View

Interestingly, they mention having 40 feet clear between the columns, to allow construction of a "subway" at some time in the future.

The diagram posted by ardecila in this post earlier in this thread. The dashed line seems to indicate the extent of the viaduct.

Plus if you look at the pavement on Canal Street north of Van Buren, the expansion joints are only half the width of the street. Between Van Buren and Harrison, the viaduct was probably already torn down and rebuilt once when Congress Parkway was punched through the old Post Office building, so who knows what it looks like under there. South of Harrison, I agree that it seems like a full-width viaduct, but that segment has little or no relevance to Union Station.

I'm not sure exactly. Images of Tracks 1 and 2 show a poured-concrete wall along the west side of the train yard. This wall runs down the middle of Canal Street. If there were open space behind it, then one would expect to see a wall built of columns with infill panels between each one. The poured-concrete wall, on the other hand, looks like the type used as a retaining wall around the city, which would indicate that there is soil behind the wall.

Mr. D, recall that 'subway' once referred to an underground pedestrian walkway (and still does in England). Station planners probably anticipated the need to connect to the Metropolitan West Side L station that used to be where the parking garage is now, so the aforementioned subway is probably the parking garage passageway. That passageway appears to be behind the same concrete wall I mentioned above, with some windows cut out of it.

A 40' span would only take it out to half the width of Canal Street, which you yourself said is 80'.

None of this proves anything, of course. I'll be thrilled if there is a ton of unused open space underneath Canal, because it will make expansion much, much easier. It's entirely possible that it exists and we've just never heard about it - the three streetcar tunnels are documented but virtually nobody knows about them, or speaks about them if they do. It was a little weird when I saw the Wacker Drive website include a construction photo from the Washington tunnel - like I was seeing into the warehouse from Raiders of the Lost Ark or something.

http://farm3.staticflickr.com/2652/5...e36e2f68_z.jpg
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